Robot control apparatus capable of transferring workpiece having parameter exceeding rated workpiece parameter

Abstract

A robot control apparatus includes a setting unit which sets a workpiece parameter, which is a parameter of a workpiece itself and affects transferability of the workpiece transferred by the industrial robot, a storage unit which stores a rated workpiece parameter, which is a maximum parameter of the workpiece itself which can be transferred by the robot at a rated velocity, and a velocity limiting unit which reduces the maximum velocity of the industrial robot to a value lower than the rated velocity when the workpiece parameter set by the setting unit exceeds the rated workpiece parameter stored in the storage unit.

The invention claimed is: 
     
       1. A robot control apparatus, comprising:
 a processor configured to set a workpiece parameter value of a parameter of a workpiece, wherein the parameter affects transferability of the workpiece to be held and transferred by an arm of an industrial robot; and 
 a memory configured to store
 a rated workpiece parameter value, which is a maximum value of the parameter at which the workpiece is transferable by the industrial robot at a rated velocity of the industrial robot; and 
 an upper-limit workpiece parameter value, which is an upper-limit value of the parameter of the workpiece transferrable by the arm of the industrial robot, and is greater than the rated workpiece parameter value, 
 
 wherein 
 the parameter of the workpiece includes a first parameter of the workpiece and a second parameter of the workpiece, the second parameter being different from the first parameter of the workpiece, and 
 the processor is configured to, in response to the set workpiece parameter value being greater than the stored rated workpiece parameter value and not greater than the upper-limit workpiece parameter value, for the first and second parameters, calculate a reduced maximum velocity of the industrial robot by
 calculating a first maximum velocity with respect to the first parameter and a second maximum velocity with respect to the second parameter, 
 determining which one of the first and second maximum velocities has a smaller value, 
 setting the smaller value as the reduced maximum velocity of the industrial robot, the reduced maximum velocity being lower than the rated velocity, and 
 causing the industrial robot to transfer the workpiece at the reduced maximum velocity. 
 
 
     
     
       2. The robot control apparatus according to  claim 1 , wherein
 the processor is configured to calculate the reduced maximum velocity of the industrial robot that is the value lower than the rated velocity by a larger amount as the workpiece parameter value set by the processor exceeds the rated workpiece parameter value stored in the memory by a larger amount. 
 
     
     
       3. The robot control apparatus according to  claim 1 , wherein the processor is configured to limit acceleration and deceleration of the industrial robot when the workpiece parameter value set by the processor is greater than the rated workpiece parameter value stored in the memory. 
     
     
       4. The robot control apparatus according to  claim 1 , wherein the first parameter of the workpiece includes a mass of the workpiece, and the second parameter of the workpiece includes an inertia of the workpiece. 
     
     
       5. The robot control apparatus according to  claim 1 , wherein
 the processor is configured to stop operation of the industrial robot when the workpiece parameter value set by the processor is greater than the upper-limit workpiece parameter value stored in the memory. 
 
     
     
       6. The robot control apparatus according to  claim 1 , wherein
 in response to the set workpiece parameter value being greater than the stored rated workpiece parameter value and less than the upper-limit workpiece parameter value, the processor is configured to calculate the reduced maximum velocity of the industrial robot. 
 
     
     
       7. The robot control apparatus according to  claim 1 , wherein the set workpiece parameter value includes a first set workpiece parameter value for the first parameter and a second set workpiece parameter value for the second parameter.